7007967: DefaultRowSorter: incorrect sorting due to not updating comparator cache

Reviewed-by: serb, jdv

src/java.desktop/share/classes/javax/swing/DefaultRowSorter.java

@@ -1033,8 +1033,10 @@ public abstract class DefaultRowSorter<M, I> extends RowSorter<M> {
             // Not transformed, nothing to do.
             return false;
         }
-        if (!sorted || (lastRow - firstRow) > viewToModel.length / 10) {
-            // We either weren't sorted, or to much changed, sort it all
+        if (!sorted || viewToModel.length == 0 ||
+                (lastRow - firstRow) > viewToModel.length / 10) {
+            // We either weren't sorted, or to much changed, sort it all or
+            // this is the first row added and we have to update diffeent caches
             sort();
             return false;
         }

test/jdk/javax/swing/JTable/DefaultRowSorterCacheTest.java

@@ -0,0 +1,102 @@
+/*
+ * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @key headful
+ * @bug 7007967
+ * @summary Verifies that DefaultRowSorter updates its cache properly when the
+ *           all the row are deleted and then new rows are added to the table
+ * @run main DefaultRowSorterCacheTest
+ */
+
+
+import javax.swing.table.DefaultTableModel;
+import javax.swing.table.TableRowSorter;
+import javax.swing.SwingUtilities;
+
+class CustomTableModel extends DefaultTableModel
+{
+    public CustomTableModel(Object[][] data, Object[] columnNames) {
+        super(data, columnNames);
+    }
+
+    @Override
+    public Class<?> getColumnClass(int columnIndex) {
+        if (getRowCount() > 0) {
+            return getValueAt(0, columnIndex).getClass();
+        }
+        return super.getColumnClass(columnIndex);
+    }
+}
+
+public class DefaultRowSorterCacheTest {
+
+    public void testSort() {
+        Object[] values = new Object[]{1, 2, 10};
+        Object[][] data = new Object[][]{{values[0]}, {values[1]}, {values[2]}};
+
+        //Create custom table model
+        DefaultTableModel model = new CustomTableModel(data, new Object[]{"A"});
+
+        TableRowSorter<DefaultTableModel> rowSorter =
+                new TableRowSorter<DefaultTableModel>(model);
+        rowSorter.toggleSortOrder(0);
+
+        for (int row = 0; row < model.getRowCount(); row++) {
+            // values are in sorted ascending. so the row index and
+            // view index from sorter should be same
+            if (row != rowSorter.convertRowIndexToView(row)) {
+                throw new RuntimeException("Wrong sorting before making any " +
+                        "changes in test case");
+            }
+        }
+
+        // clear model and notify sorter
+        model.setRowCount(0);
+        rowSorter.rowsDeleted(0, values.length - 1);
+
+        // refill the model and notify sorter
+        for (int i = 0; i < values.length; i++) {
+            model.addRow(new Object[]{values[i]});
+            rowSorter.rowsInserted(i, i);
+        }
+
+        for (int row = 0; row < model.getRowCount(); row++) {
+            // values are in sorted ascending. so the row index and
+            // view index from sorter should be same
+            if (row != rowSorter.convertRowIndexToView(row)) {
+                throw new RuntimeException("Wrong sorting at end of test case");
+            }
+        }
+    }
+
+    public static void main(String[] args) throws Exception{
+        SwingUtilities.invokeAndWait(new Runnable() {
+            @Override
+            public void run() {
+                new DefaultRowSorterCacheTest().testSort();
+            }
+        });
+    }
+}